1. Field of the Invention
The present invention relates generally to the field of medicine. More particularly, it concerns antimicrobial films and coverings for medical devices, and related methods.
2. Description of Related Art
Breast reconstruction is frequently performed following mastectomies. Breast implants or tissue expanders are frequently used. Infection is a significant problem associated with breast implants and tissue expanders for recovering cancer patients. Infection rates for reconstruction cases have been estimated to range from 2-24% (Pittet et al.). Other than the direct systemic complications of infection, local complications can cause discomfort, cosmesis, capsule formation and hardening and can lead to implant removal or replacement. Current protocol is to bathe breast implant and tissue expander devices in an aqueous solution of three different antibiotics for 5-15 minutes prior to insertion. Most implants are made from silicone rubber which is highly hydrophobic so the antibiotic solution rolls off the device after it is removed from the antibiotic bath, hence very little antibiotic is actually carried into the implant tissue pocket following insertion. In a retrospective study of breast implant infections following reconstructive surgery, 79% of cases had appropriate antibiotic irrigation performed prior to placement but 63% had breakthrough infections despite that (Viola et al., 2014).
Following insertion, a drainage catheter is usually left in place for a week or so which can be a conduit for bacterial access to the device. Furthermore, although the skin flap is eventually closed, breast tissue has high levels of endogenous bacterial flora that can access and colonize the device. The factors create a prolonged need for infection protection beyond the insertion procedure itself that is not met using the current standard of care. The bathing procedure adds to valuable OR time and because of the size of the implant, significant volumes of antibiotic solution are required to bathe the implant. Clearly, there is a need for methods for reducing the risk of infection associated with implanting a medical device or prosthesis, such as a breast implant.